HIT antibody has high false positive

• related: heparin induced thrombocytopenia and thrombosis HIT
• tags: #permanent

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HIT antibody detects PF4 heparin antibody but not if they can activate platelets. These are widely available tests but have high false positivity.

Higher optical density (OD) unit with the HIT test has higher likelihood of HIT. >2 OD usually means HIT is confirmed.¹

Use serotonin release assay to determine HIT in indeterminate HIT antibody test.

Links to this note

• heparin induced thrombocytopenia and thrombosis HIT
  • HIT antibody has high false positive

Footnotes

1. https://www.uptodate.com/contents/clinical-presentation-and-diagnosis-of-heparin-induced-thrombocytopenia ↩